docs: def run(self, default=None):
          """Parse the command line arguments.
  
          default:
              Name of default command to run if no arguments are passed.
  
          """
          parent, *sys_args = sys.argv
          self.parent = Path(parent).stem
          cmd_name = default
          if sys_args:
              cmd_name, *sys_args = sys_args
  
          if cmd_name is None or cmd_name.lstrip("-") in HELP_COMMANDS:
              self.show_help_root()
              return
  
          command = self.commands.get(cmd_name)
          if command is None:
              self.show_error(f"command `{cmd_name}` not found")
              self.show_help_root()
              return
  
          args, opts = parse_args(sys_args)
          return command.run(*args, **opts)